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Test::Simple(3)	       Perl Programmers	Reference Guide	       Test::Simple(3)

       Test::Simple - Basic utilities for writing tests.

	 use Test::Simple tests	=> 1;

	 ok( $foo eq $bar, 'foo	is bar'	);

       ** If you are unfamiliar	with testing read Test::Tutorial first!	**

       This is an extremely simple, extremely basic module for writing tests
       suitable	for CPAN modules and other pursuits.  If you wish to do	more
       complicated testing, use	the Test::More module (a drop-in replacement
       for this	one).

       The basic unit of Perl testing is the ok.  For each thing you want to
       test your program will print out	an "ok"	or "not	ok" to indicate	pass
       or fail.	 You do	this with the "ok()" function (see below).

       The only	other constraint is you	must pre-declare how many tests	you
       plan to run.  This is in	case something goes horribly wrong during the
       test and	your test program aborts, or skips a test or whatever.	You do
       this like so:

	   use Test::Simple tests => 23;

       You must	have a plan.

	     ok( $foo eq $bar, $name );
	     ok( $foo eq $bar );

	   "ok()" is given an expression (in this case "$foo eq	$bar").	 If
	   it's	true, the test passed.	If it's	false, it didn't.  That's
	   about it.

	   "ok()" prints out either "ok" or "not ok" along with	a test number
	   (it keeps track of that for you).

	     # This produces "ok 1 - Hell not yet frozen over" (or not ok)
	     ok( get_temperature($hell)	> 0, 'Hell not yet frozen over'	);

	   If you provide a $name, that	will be	printed	along with the "ok/not
	   ok" to make it easier to find your test when	if fails (just search
	   for the name).  It also makes it easier for the next	guy to
	   understand what your	test is	for.  It's highly recommended you use
	   test	names.

	   All tests are run in	scalar context.	 So this:

	       ok( @stuff, 'I have some	stuff' );

	   will	do what	you mean (fail if stuff	is empty)

       Test::Simple will start by printing number of tests run in the form
       "1..M" (so "1..5" means you're going to run 5 tests).  This strange
       format lets Test::Harness know how many tests you plan on running in
       case something goes horribly wrong.

       If all your tests passed, Test::Simple will exit	with zero (which is
       normal).	 If anything failed it will exit with how many failed.	If you
       run less	(or more) tests	than you planned, the missing (or extras) will
       be considered failures.	If no tests were ever run Test::Simple will
       throw a warning and exit	with 255.  If the test died, even after	having
       successfully completed all its tests, it	will still be considered a
       failure and will	exit with 255.

       So the exit codes are...

	   0		       all tests successful
	   255		       test died or all	passed but wrong # of tests run
	   any other number    how many	failed (including missing or extras)

       If you fail more	than 254 tests,	it will	be reported as 254.

       This module is by no means trying to be a complete testing system.
       It's just to get	you started.  Once you're off the ground its
       recommended you look at Test::More.

       Here's an example of a simple .t	file for the fictional Film module.

	   use Test::Simple tests => 5;

	   use Film;  #	What you're testing.

	   my $btaste =	Film->new({ Title    =>	'Bad Taste',
				    Director =>	'Peter Jackson',
				    Rating   =>	'R',
				    NumExplodingSheep => 1
	   ok( defined($btaste)	&& ref $btaste eq 'Film',     'new() works' );

	   ok( $btaste->Title	   eq 'Bad Taste',     'Title()	get'	);
	   ok( $btaste->Director   eq 'Peter Jackson', 'Director() get'	);
	   ok( $btaste->Rating	   eq 'R',	       'Rating() get'	);
	   ok( $btaste->NumExplodingSheep == 1,	       'NumExplodingSheep() get' );

       It will produce output like this:

	   ok 1	- new()	works
	   ok 2	- Title() get
	   ok 3	- Director() get
	   not ok 4 - Rating() get
	   #   Failed test 'Rating() get'
	   #   in t/film.t at line 14.
	   ok 5	- NumExplodingSheep() get
	   # Looks like	you failed 1 tests of 5

       Indicating the Film::Rating() method is broken.

       Test::Simple will only report a maximum of 254 failures in its exit
       code.  If this is a problem, you	probably have a	huge test script.
       Split it	into multiple files.  (Otherwise blame the Unix	folks for
       using an	unsigned short integer as the exit status).

       Because VMS's exit codes	are much, much different than the rest of the
       universe, and perl does horrible	mangling to them that gets in my way,
       it works	like this on VMS.

	   0	 SS$_NORMAL	   all tests successful
	   4	 SS$_ABORT	   something went wrong

       Unfortunately, I	can't differentiate any	further.

       Test::Simple is explicitly tested all the way back to perl 5.6.0.

       Test::Simple is thread-safe in perl 5.8.1 and up.

       This module was conceived while talking with Tony Bowden	in his kitchen
       one night about the problems I was having writing some really
       complicated feature into	the new	Testing	module.	 He observed that the
       main problem is not dealing with	these edge cases but that people hate
       to write	tests at all.  What was	needed was a dead simple module	that
       took all	the hard work out of testing and was really, really easy to
       learn.  Paul Johnson simultaneously had this idea (unfortunately, he
       wasn't in Tony's	kitchen).  This	is it.

	   More	testing	functions!  Once you outgrow Test::Simple, look	at
	   Test::More.	Test::Simple is	100% forward compatible	with
	   Test::More (i.e. you	can just use Test::More	instead	of
	   Test::Simple	in your	programs and things will still work).

       Look in Test::More's SEE	ALSO for more testing modules.

       Idea by Tony Bowden and Paul Johnson, code by Michael G Schwern
       <>, wardrobe by	Calvin Klein.

       Chad Granum <>

       Copyright 2001-2008 by Michael G	Schwern	<>.

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.


perl v5.28.3			  2020-05-14		       Test::Simple(3)


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